Polypeptide with broad biological activity: isolation from small intestine

A polypeptide, which has potent and diverse biological action-including systemic vasodilation, hypotension, increased cardiac output, respiratory stimulation, and hyperglycemia-was isolated from the small intestine of the hog. The peptide has 28 amino acid residues and is chemically distinct from the kinins, "substance P," glucagon, and secretin.     

Herpesvirus hominis: isolation from human trigeminal ganglion

Herpesvirus hominis was isolated from the trigeminal ganglion obtained at autopsy from 1 of 22 patients with no clinical evidence of active herpetic disease, and from one patient with malignant lymphoma who died with herpes zoster on the abdomen, pulmonary cytomegalic inclusion disease, and possible oral herpes simplex. Virus was isolated by cocultivation of explants of ganglion with monolayers of Vero green monkey kidney cells and required 3 weeks of culture before viral cytopathic effects were evident. These observations support the concept that latent infection of sensory ganglia may be the source of virus in recurrent herpetic disease in man.     

覆盆子糖蛋白提取工艺的研究

[目的]研究中药覆盆子糖蛋白的最佳提取工艺。[方法]采用热水提取法提取覆盆子糖蛋白,考察了料液比、提取温度、提取时间和提取次数对覆盆子糖蛋白得率的影响。在此基础上,考察了超声波辅助热水提取各因素对糖蛋白得率的影响。[结果]结果表明,在料液比1：15、提取温度为50℃、提取时间4h、提取次数2次的条件下,覆盆子糖蛋白得率最高。经超声波处理后覆盆子糖蛋白得率明显增加,超声波处理频率60kHz,功率140W,超声时间为20min,糖蛋白得率最高。[结论]超声波辅助提取法工艺操作简单,成本较低,提取率较高,适于大规模生产,也可将此法提取到的糖蛋白进一步地纯化以用于后续试验研究。     

Axons: isolation from mammalian central nervous system

Centrifugation of a homogenate of white matter, in a solution of buffered sucrose containing salt, produces a floating layer of myelinated axons. When these are suspended in hypotonic buffer, the mnyelin swells and strips away from the axon. Axons are then separated from the myelin by centrifugation. The resulting preparation consists of a variable population of processes with lengths up to 200 micrometers and diameters between 0.3 and 5.0 micrometers. The axons contain neurofilaments and mitochondria, although no axolemma or neurotubules are evident. The preparation contains cerebroside and sulfatide, yet is essentially free of myelin.     

Sweet-sensitive protein from bovine taste buds: isolation and assay

Using refractometry and ultraviolet-difference spectroscopy to indicate interaction between proteins and coinpounds of low molecular weight, we found a protein fraction in bovine tongue extracts that coinplexes sugars and saccharin. The strengths of the coinzplexes parallel the degrees of sweetness of the compounds, and the effects of pH upon formation of complexes parallel the effects of pH upon sensitivity of taste buds to sweet compounds in vivo.     

Lactoperoxidase: identification and isolation from Harderian and lacrimal glands

Investigation of bovine lacrimal and harderian glands revealed the presence of the enzyme lactoperoxidase, which was isolated and purified. A nonheme, iron-containing protein was identified at the same time. Both proteins are present in milk, mammary glands, and salivary glands. Their roles are discussed: The lactoperoxidase may be important in controlling bacterial flora.     

Isoantigenic variants: isolation from human diploid cells in culture

Variant human fibroblast substrains, resistant to a cytotoxic human isoantiserum, were isolated from sensitive strains by repeated exposure to isoantiserum and rabbit complement. The resistant phenotype was stable, apparently occurred at low frequency, and was associated with loss of surface isoantigens.     

摩擦滑移隔震结构的减震分析

研究了摩擦滑移支撑结构的动力响应，采用Newmark法，对一个算例结构在加摩擦隔震前，后两种情况下，分别进行了动力反应分析和比较。结果表明，摩擦滑移隔震技术具有明显的隔震效果。     

Triterpene alcohol isolation from oil shale

Isoarborinol, an intact pentacyclic unsaturated alcohol, was isolated from the Messel oil shale (about 50 x 106 years old). Complex organic substances, even those very sensitive to oxidation, reduction, or acidic conditions, can thus survive without alteration for long periods.     

Virus of the California encephalitis complex: isolation from Culiseta inornata

A virus of the California encephalitis complex was isolated from two pools of the mosquito Culiseta inornata, collected in mammalian burrows of Alberta during the summer of 1965. This is the first recorded isolation of California encephalitis virus from mosquitoes in Canada.     

Pheromones: isolation of male sex attractants from a female primate

Fractionation of vaginal secretions from rhesus monkeys by partitioning and chromatographic procedures, combined with behavioral studies, demonstrates that short-chain aliphatic acids are responsible for stimulating the sexual behavior of males. Injection of estradiol into ovariectomized females increases the concentration of volatile acids in secretions which will then sexually stimulate these male primates.     

Milker''s nodules: isolation of a poxvirus from a human case

A virus of the pox group was isolated from a lesion on a patient with milker's nodules by use of tissue cultures of bovine cells. The virus shows marked biologic and serologic differences from vaccinia virus, and it is presumably the etiologic agent of the milker's nodule syndrome.     

Plasma membranes: isolation from naturally fused and lysolecithin-treated muscle cells

A medium containing bicarbonate and calcium was used to isolate plasma membranes of cultured muscle cells. Membranes from differentiated myotubes, as well as the labile, largely unfused, lysolecithin-treated cells from the same culture could be isolated by identical manipulations. Adenylate cyclase of high specific activity was assayed in plasma membranes from both types of cells. Lysolecithin treatment apparently interferes with the metabolism and turnover of membrane phospholipids and thus prevents the natural fusion of muscle cells.     

Algal virus: isolation

Freshwater blue-green algae of the genera Lyngbya, Plectonema, and Phormidium are susceptible to a virus recently isolated from a waste-stabilization pond. Electron micrographs of a partially purified preparation show that the viral particle has an icosahedral structure about 66 mmicro in diameter.     

Evoked release of norepinephrine and serotonin from brain slices: inhibitoon by lithium

Slices of mammalian brain accumulate H(3)-norepinephrine and H(3)-serotonin when incubated in a physiologic medium containing these tritiated monoamines. When these tissues are subjected to mild electrical stimulation of short duration, which is associated with depolarization of nerve membranes, a striking increase in the rate of efflux of the exogenous labeled monoamines occurs. Stimulation-induced release of both labeled monoamines is diminished by the presence of lithium ions in the perfusing medium; related monovalent cations had no such effect. Evoked release from slices of brain from animals treated intraperitoneally with lithium chloride for 3 days was also reduced.     

Rechargeable lithium batteries with aqueous electrolytes

Rechargeable lithium-ion batteries that use an aqueous electrolyte have been developed. Cells with LiMn(2)O(4) and VO(2)(B) as electrodes and 5 M LiNO(3) in water as the electrolyte provide a fundamentally safe and cost-effective technology that can compete with nickelcadmium and lead-acid batteries on the basis of stored energy per unit of weight.     

Yeast RNA polymerase II genes: isolation with antibody probes

Genes encoding yeast RNA polymerase II subunits were cloned. Efficient isolation of these genes was accomplished by probing a phage lambda gt11 recombinant DNA expression library with polyvalent antibodies directed against purified yeast RNA polymerase II. The identity of genes that specify the largest RNA polymerase II subunits, the 220,000- and 150,000-dalton polypeptides, was confirmed by competitive radioimmune assay. Both of these genes exist in single copy in the yeast Saccharomyces cerevisiae.     

Rapid evolution of reproductive isolation in the wild: evidence from introduced salmon

Colonization of new environments should promote rapid speciation as a by-product of adaptation to divergent selective regimes. Although this process of ecological speciation is known to have occurred over millennia or centuries, nothing is known about how quickly reproductive isolation actually evolves when new environments are first colonized. Using DNA microsatellites, population-specific natural tags, and phenotypic variation, we tested for reproductive isolation between two adjacent salmon populations of a common ancestry that colonized divergent reproductive environments (a river and a lake beach). We found evidence for the evolution of reproductive isolation after fewer than 13 generations.     

Tarichatoxin: isolation and purification

The potent neurotoxin occurring in the embryos of the California newt, Taricha torosa, has been obtained in crystalline form. With a lethal subcutaneous dose of approximately 0.14 micrograms for a 20-gram mouse, it is, along with saxitoxin and tetrodotoxin, one of the most toxic nonprotein substances known.